The court heard that a document filled in by a nurse who carried out the blood test on Redknapp at the police station had been "tampered with" or "altered" after she had completed and signed it.

Nurse Julie Pinnock had failed to enter the time the test was carried out at in error.

The copy of the form originally submitted in court had the time on it but today Ms Pinnock said it was not her handwriting and she had missed out the time on the original.

Mr Lucas said this called into question the admissibility of that form but also the integrity of other documents that had been submitted, including a form which listed an evidence bag serial number which did not appear to match the numbers on the blood vial or plastic container surrounding it.

CAUGHT: Redknapp's eyes were said to be 'droopy' (Pic: Graham Hunt/BNPS)

Lucas added that the defence's "lingering doubts" about the mysterious evidence bag number were amplified when they found out today the form was altered.

He also described the case as an "unsatisfactory state of affairs" at Poole Magistrates' Court.

He said: "This is to do with the integrity of documentary evidence in this case. We have established that one of the documents has been tampered with and there is no explanation for the tampering.

"That's behaviour this court should not put up with. It's the responsibility of the court to protect the fairness of these proceedings.

POSITIVE: Cocaine derivative benzoylecgonine was found in Redknapp's system (Pic: Graham Hunt/BNPS)

“Something has gone on in the background that plainly shouldn't have and that undermines the prosecution's case”

Phillip Lucas

"I would say this is an extreme situation. It casts doubt on the other documents in this case. Something has gone on in the background that plainly shouldn't have and that undermines the prosecution's case."

Charles Nightingale, prosecuting, said there would be an investigation into how the form came to be altered but said the time being added was not a critical fact and did not fundamentally undermine the evidence.

Nightingale added that the prosecution felt there was still a quite clear case for the defendant to answer.

District Judge Stephen Nicholls said he would need time to consider the arguments and would issue a written ruling in the week of April 29.

A previous hearing heard that Redknapp, the older brother of former Liverpool and England footballer and Sky Sports pundit Jamie Redknapp, was stopped by police at 8pm on April 2 last year in the affluent Canford Cliffs area of Poole.

It was alleged that his eyes were "droopy" and he was cleaning his tongue with his teeth.

He was arrested after testing positive for a road side drug test.

Redknapp, from Poole, denies a charge of driving a vehicle while over the specified drug limit.